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  <div class="section" id="set">
<span id="command:set"></span><h1>set<a class="headerlink" href="#set" title="Permalink to this headline">¶</a></h1>
<p>Set a normal, cache, or environment variable to a given value.
See the <a class="reference internal" href="../manual/cmake-language.7.html#cmake-language-variables"><span class="std std-ref">cmake-language(7) variables</span></a>
documentation for the scopes and interaction of normal variables
and cache entries.</p>
<p>Signatures of this command that specify a <code class="docutils literal notranslate"><span class="pre">&lt;value&gt;...</span></code> placeholder
expect zero or more arguments.  Multiple arguments will be joined as
a <a class="reference internal" href="../manual/cmake-language.7.html#cmake-language-lists"><span class="std std-ref">semicolon-separated list</span></a> to form the actual variable
value to be set.  Zero arguments will cause normal variables to be
unset.  See the <span class="target" id="index-0-command:unset"></span><a class="reference internal" href="unset.html#command:unset" title="unset"><code class="xref cmake cmake-command docutils literal notranslate"><span class="pre">unset()</span></code></a> command to unset variables explicitly.</p>
<div class="section" id="set-normal-variable">
<h2>Set Normal Variable<a class="headerlink" href="#set-normal-variable" title="Permalink to this headline">¶</a></h2>
<div class="highlight-cmake notranslate"><div class="highlight"><pre><span></span><span class="nf">set(</span><span class="nv">&lt;variable&gt;</span><span class="w"> </span><span class="nv">&lt;value&gt;...</span><span class="w"> </span><span class="p">[</span><span class="no">PARENT_SCOPE</span><span class="p">]</span><span class="nf">)</span><span class="w"></span>
</pre></div>
</div>
<p>Sets the given <code class="docutils literal notranslate"><span class="pre">&lt;variable&gt;</span></code> in the current function or directory scope.</p>
<p>If the <code class="docutils literal notranslate"><span class="pre">PARENT_SCOPE</span></code> option is given the variable will be set in
the scope above the current scope.  Each new directory or function
creates a new scope.  This command will set the value of a variable
into the parent directory or calling function (whichever is applicable
to the case at hand). The previous state of the variable’s value stays the
same in the current scope (e.g., if it was undefined before, it is still
undefined and if it had a value, it is still that value).</p>
</div>
<div class="section" id="set-cache-entry">
<h2>Set Cache Entry<a class="headerlink" href="#set-cache-entry" title="Permalink to this headline">¶</a></h2>
<div class="highlight-cmake notranslate"><div class="highlight"><pre><span></span><span class="nf">set(</span><span class="nv">&lt;variable&gt;</span><span class="w"> </span><span class="nv">&lt;value&gt;...</span><span class="w"> </span><span class="no">CACHE</span><span class="w"> </span><span class="nv">&lt;type&gt;</span><span class="w"> </span><span class="nv">&lt;docstring&gt;</span><span class="w"> </span><span class="p">[</span><span class="no">FORCE</span><span class="p">]</span><span class="nf">)</span><span class="w"></span>
</pre></div>
</div>
<p>Sets the given cache <code class="docutils literal notranslate"><span class="pre">&lt;variable&gt;</span></code> (cache entry).  Since cache entries
are meant to provide user-settable values this does not overwrite
existing cache entries by default.  Use the <code class="docutils literal notranslate"><span class="pre">FORCE</span></code> option to
overwrite existing entries.</p>
<p>The <code class="docutils literal notranslate"><span class="pre">&lt;type&gt;</span></code> must be specified as one of:</p>
<dl class="simple">
<dt><code class="docutils literal notranslate"><span class="pre">BOOL</span></code></dt><dd><p>Boolean <code class="docutils literal notranslate"><span class="pre">ON/OFF</span></code> value.  <span class="target" id="index-0-manual:cmake-gui(1)"></span><a class="reference internal" href="../manual/cmake-gui.1.html#manual:cmake-gui(1)" title="cmake-gui(1)"><code class="xref cmake cmake-manual docutils literal notranslate"><span class="pre">cmake-gui(1)</span></code></a> offers a checkbox.</p>
</dd>
<dt><code class="docutils literal notranslate"><span class="pre">FILEPATH</span></code></dt><dd><p>Path to a file on disk.  <span class="target" id="index-1-manual:cmake-gui(1)"></span><a class="reference internal" href="../manual/cmake-gui.1.html#manual:cmake-gui(1)" title="cmake-gui(1)"><code class="xref cmake cmake-manual docutils literal notranslate"><span class="pre">cmake-gui(1)</span></code></a> offers a file dialog.</p>
</dd>
<dt><code class="docutils literal notranslate"><span class="pre">PATH</span></code></dt><dd><p>Path to a directory on disk.  <span class="target" id="index-2-manual:cmake-gui(1)"></span><a class="reference internal" href="../manual/cmake-gui.1.html#manual:cmake-gui(1)" title="cmake-gui(1)"><code class="xref cmake cmake-manual docutils literal notranslate"><span class="pre">cmake-gui(1)</span></code></a> offers a file dialog.</p>
</dd>
<dt><code class="docutils literal notranslate"><span class="pre">STRING</span></code></dt><dd><p>A line of text.  <span class="target" id="index-3-manual:cmake-gui(1)"></span><a class="reference internal" href="../manual/cmake-gui.1.html#manual:cmake-gui(1)" title="cmake-gui(1)"><code class="xref cmake cmake-manual docutils literal notranslate"><span class="pre">cmake-gui(1)</span></code></a> offers a text field or a
drop-down selection if the <span class="target" id="index-0-prop_cache:STRINGS"></span><a class="reference internal" href="../prop_cache/STRINGS.html#prop_cache:STRINGS" title="STRINGS"><code class="xref cmake cmake-prop_cache docutils literal notranslate"><span class="pre">STRINGS</span></code></a> cache entry
property is set.</p>
</dd>
<dt><code class="docutils literal notranslate"><span class="pre">INTERNAL</span></code></dt><dd><p>A line of text.  <span class="target" id="index-4-manual:cmake-gui(1)"></span><a class="reference internal" href="../manual/cmake-gui.1.html#manual:cmake-gui(1)" title="cmake-gui(1)"><code class="xref cmake cmake-manual docutils literal notranslate"><span class="pre">cmake-gui(1)</span></code></a> does not show internal entries.
They may be used to store variables persistently across runs.
Use of this type implies <code class="docutils literal notranslate"><span class="pre">FORCE</span></code>.</p>
</dd>
</dl>
<p>The <code class="docutils literal notranslate"><span class="pre">&lt;docstring&gt;</span></code> must be specified as a line of text providing
a quick summary of the option for presentation to <span class="target" id="index-5-manual:cmake-gui(1)"></span><a class="reference internal" href="../manual/cmake-gui.1.html#manual:cmake-gui(1)" title="cmake-gui(1)"><code class="xref cmake cmake-manual docutils literal notranslate"><span class="pre">cmake-gui(1)</span></code></a>
users.</p>
<p>If the cache entry does not exist prior to the call or the <code class="docutils literal notranslate"><span class="pre">FORCE</span></code>
option is given then the cache entry will be set to the given value.
Furthermore, any normal variable binding in the current scope will
be removed to expose the newly cached value to any immediately
following evaluation.</p>
<p>It is possible for the cache entry to exist prior to the call but
have no type set if it was created on the <span class="target" id="index-0-manual:cmake(1)"></span><a class="reference internal" href="../manual/cmake.1.html#manual:cmake(1)" title="cmake(1)"><code class="xref cmake cmake-manual docutils literal notranslate"><span class="pre">cmake(1)</span></code></a> command
line by a user through the <code class="docutils literal notranslate"><span class="pre">-D&lt;var&gt;=&lt;value&gt;</span></code> option without
specifying a type.  In this case the <code class="docutils literal notranslate"><span class="pre">set</span></code> command will add the
type.  Furthermore, if the <code class="docutils literal notranslate"><span class="pre">&lt;type&gt;</span></code> is <code class="docutils literal notranslate"><span class="pre">PATH</span></code> or <code class="docutils literal notranslate"><span class="pre">FILEPATH</span></code>
and the <code class="docutils literal notranslate"><span class="pre">&lt;value&gt;</span></code> provided on the command line is a relative path,
then the <code class="docutils literal notranslate"><span class="pre">set</span></code> command will treat the path as relative to the
current working directory and convert it to an absolute path.</p>
</div>
<div class="section" id="set-environment-variable">
<h2>Set Environment Variable<a class="headerlink" href="#set-environment-variable" title="Permalink to this headline">¶</a></h2>
<div class="highlight-cmake notranslate"><div class="highlight"><pre><span></span><span class="nf">set(</span><span class="o">ENV{</span><span class="nt">&lt;variable&gt;</span><span class="o">}</span><span class="w"> </span><span class="p">[</span><span class="nv">&lt;value&gt;</span><span class="p">]</span><span class="nf">)</span><span class="w"></span>
</pre></div>
</div>
<p>Sets an <span class="target" id="index-0-manual:cmake-env-variables(7)"></span><a class="reference internal" href="../manual/cmake-env-variables.7.html#manual:cmake-env-variables(7)" title="cmake-env-variables(7)"><code class="xref cmake cmake-manual docutils literal notranslate"><span class="pre">Environment</span> <span class="pre">Variable</span></code></a>
to the given value.
Subsequent calls of <code class="docutils literal notranslate"><span class="pre">$ENV{&lt;variable&gt;}</span></code> will return this new value.</p>
<p>This command affects only the current CMake process, not the process
from which CMake was called, nor the system environment at large,
nor the environment of subsequent build or test processes.</p>
<p>If no argument is given after <code class="docutils literal notranslate"><span class="pre">ENV{&lt;variable&gt;}</span></code> or if <code class="docutils literal notranslate"><span class="pre">&lt;value&gt;</span></code> is
an empty string, then this command will clear any existing value of the
environment variable.</p>
<p>Arguments after <code class="docutils literal notranslate"><span class="pre">&lt;value&gt;</span></code> are ignored. If extra arguments are found,
then an author warning is issued.</p>
</div>
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  <h3><a href="../index.html">Table of Contents</a></h3>
  <ul>
<li><a class="reference internal" href="#">set</a><ul>
<li><a class="reference internal" href="#set-normal-variable">Set Normal Variable</a></li>
<li><a class="reference internal" href="#set-cache-entry">Set Cache Entry</a></li>
<li><a class="reference internal" href="#set-environment-variable">Set Environment Variable</a></li>
</ul>
</li>
</ul>

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